The High-Cost-Catch (Kogaku Ryoyohi) System

The High-Cost-Catch System Japan residents rely on caps covered medical spending per calendar month by income, so a large hospital bill does not scale without limit.¹ A typical-income worker who incurs 1,000,000 JPY of covered care in one month pays about 92,940 JPY under the current formula, with the insurer absorbing the rest; that figure holds across the whole typical-income band only for treatment months to July 2027 (as of 2026-07-31).²³ This article maps the formula, the brackets, and the two payment routes.

Confirm current details with official sources

Procedures, fees, and requirements can change. Confirm current details at the Ministry of Health, Labour and Welfare (MHLW). This article is general information, not medical advice; for your specific case, consult a licensed medical provider and your insurer.

Overview

Japan public insurance normally asks patients to pay 30 percent at the counter while insurance pays 70 percent. The High-Cost-Catch adds a second cap on top of that share for covered care in a single month.¹

Once monthly covered copayments pass a personal ceiling, the excess comes back from the insurer or is never charged. The ceiling follows age and income, and the system covers every enrolled resident the same way.¹⁴

Who is already covered

The 高額療養費制度 (kogaku ryoyohi seido, "high-cost medical expense benefit system") is built into both public schemes, so there is no separate signup.⁴ Employees use health insurance through Kyokai Kenpo or a company society, while self-employed residents and others use National Health Insurance at the ward or municipal office.²

Anyone staying 3 months or more must enroll in one scheme and then holds the same protection regardless of nationality.¹ To find the right counter, read the insurance card: a company or society name points to that insurer, a municipality name points to the municipal National Health Insurance counter, and a wide-area union name points to that union.¹

How the monthly cap works

The cap applies per calendar month, from the 1st to the last day, to covered treatment only.¹ The 自己負担限度額 (jiko-futan gendogaku, "monthly out-of-pocket ceiling") is the most the household pays for that month; the insurer absorbs the covered excess above it.⁴

For the upper and middle under-70 brackets, the formula is a base amount plus 1 percent of total covered cost above a threshold (as of 2026-07-31; confirm current figures with MHLW or your insurer).⁴ Total covered cost means the full 100 percent insured figure, not the 30 percent paid at the counter (as of 2026-07-31).⁴ From August 2027 the same formula covers nine finer upper and middle bands, while the three lowest taxable bands pay flat amounts (as of 2026-07-31).³

A worked example at typical income

Take a typical-income resident in bracket ウ (annual income about 3.7M to 7.7M JPY) with 1,000,000 JPY of covered care in one month. The current ceiling is 85,800 plus 1 percent of 714,000, which equals 92,940 JPY (as of 2026-07-31).²

That ceiling applies to the whole of band ウ for treatment months to July 2027. From 2027-08-01 the band splits in three, and the same 1,000,000 JPY month costs 92,940 JPY at about 3.7M to 5.1M JPY, 104,830 JPY at about 5.1M to 6.5M JPY, and 116,720 JPY at about 6.5M to 7.7M JPY (as of 2026-07-31).³

The patient share without the system would be 300,000 JPY at 30 percent. The benefit therefore covers roughly 207,000 JPY of that month (as of 2026-07-31).²

MHLW illustrates the same point with a 1,000,000 JPY treatment capped near 93,000 JPY for an under-70 resident with annual income of about 3.7M to 5.1M JPY (as of 2026-07-31).¹ MHLW uses that narrower range because it is the August 2027 sub-band that keeps the 85,800 JPY formula; until July 2027 the same formula covers the whole 3.7M to 7.7M JPY band.³ Confirm your band with your insurer before relying on either illustration.

What the formula leaves out

Only insured-treatment copayments count toward the ceiling. Extra-bed differentials, hospital meal and living costs during admission, and non-insured or advanced-care technology fees sit outside the benefit and are paid in full on top (as of 2026-07-01).⁴⁵

The MHLW English explainer lists the same exclusions, including private-room charges, pajama rental, food service, and non-covered advanced care.⁶ Review before admission can reduce these extra charges, since they carry no upper limit.

Budget private-room and meal charges outside the monthly ceiling

The monthly ceiling never covers the private-room differential or hospital meals. A capped treatment month can still produce a large bill when these extras stack on top.⁴⁵

Income brackets and ceilings

Ceilings step by income band and age, with five under-70 bands labeled ア to オ for treatment months from August 2026 to July 2027 (as of 2026-07-31; confirm current figures with MHLW or your insurer).³⁷ The formula is set nationally, so the same table applies anywhere in Japan and only the application counter differs by insurer. The current table below shows both the pre-reform month ceilings and the August 2026 ones, since treatment months before and after August 2026 use different bases.

Band	NHI income basis	Monthly ceiling to July 2026	Monthly ceiling Aug 2026 to Jul 2027	As of	Multiple-occurrence
ア	over 9.01M JPY	252,600 + (cost minus 842,000) x 1%	270,300 + (cost minus 901,000) x 1%	2026-07-3132	140,100
イ	6.0M to 9.01M JPY	167,400 + (cost minus 558,000) x 1%	179,100 + (cost minus 597,000) x 1%	2026-07-3132	93,000
ウ	2.1M to 6.0M JPY	80,100 + (cost minus 267,000) x 1%	85,800 + (cost minus 286,000) x 1%	2026-07-3132	44,400
エ	up to 2.1M JPY	57,600	61,500	2026-07-3132	44,400
オ	residence-tax-exempt household	35,400	36,900	2026-07-3132	24,600

A cabinet order, 健康保険法施行令等の一部を改正する政令 (Kenkō Hoken-hō Shikōrei-tō no Ichibu o Kaisei suru Seirei, "Cabinet Order Partially Amending the Health Insurance Act Enforcement Order and Related Orders"; 令和8年政令第240号), promulgated on 2026-07-29, fixes a second stage that takes effect on 2027-08-01.⁸⁹ From that date the four taxable bands each split into three, giving 13 bands in all (as of 2026-07-31).³ The table below lists the new bands by income range.

Annual income (approx.)	NHI income basis	Monthly ceiling from Aug 2027	Multiple-occurrence	Annual cap
16.5M JPY or more	over 13.56M JPY	342,000 + (cost minus 1,140,000) x 1%	140,100	1,680,000
14.1M to 16.5M JPY	11.10M to 13.56M JPY	303,000 + (cost minus 1,010,000) x 1%	140,100	1,680,000
11.6M to 14.1M JPY	9.01M to 11.10M JPY	270,300 + (cost minus 901,000) x 1%	140,100	1,680,000
10.4M to 11.6M JPY	8.09M to 9.01M JPY	209,400 + (cost minus 698,000) x 1%	93,000	1,110,000
9.5M to 10.4M JPY	6.79M to 8.09M JPY	194,400 + (cost minus 648,000) x 1%	93,000	1,110,000
7.7M to 9.5M JPY	6.00M to 6.79M JPY	179,100 + (cost minus 597,000) x 1%	93,000	1,110,000
6.5M to 7.7M JPY	4.10M to 6.00M JPY	110,400 + (cost minus 368,000) x 1%	44,400	530,000
5.1M to 6.5M JPY	3.13M to 4.10M JPY	98,100 + (cost minus 327,000) x 1%	44,400	530,000
3.7M to 5.1M JPY	2.10M to 3.13M JPY	85,800 + (cost minus 286,000) x 1%	44,400	530,000
2.6M to 3.7M JPY	1.27M to 2.10M JPY	69,600	44,400	530,000
2.0M to 2.6M JPY	0.86M to 1.27M JPY	65,400	44,400	530,000
up to 2.0M JPY	up to 0.86M JPY	61,500	34,500	410,000
residence-tax-exempt household	n/a	36,900	24,600	290,000

The lowest sub-band of each current band keeps its current monthly amount (270,300, 179,100, 85,800, and 61,500 JPY), and the residence-tax-exempt band does not change (as of 2026-07-31).³ Both tables follow MHLW's revision document (as of 2026-07-31).³ The income basis for National Health Insurance is prior-year income minus the 430,000 JPY basic deduction, summed across household members, with bands reset each August 1 (as of 2026-07-01).²⁵

Without a tax filing, the ward judges the band as ア, the highest bracket.² File the residence-tax return even in a zero-income year to hold the correct band.

Residents aged 70 and over

Residents aged 70 and over use a separate table with per-person outpatient caps plus household caps including admission.² Low-income bands sit lower, and the August 2026 revision added annual caps and revised outpatient caps alongside the monthly ones (as of 2026-07-31).²³ Active-earner bands have no outpatient cap and follow the under-70 formulas in both stages, though their income thresholds differ.³

Band (70 and over)	Before Aug 2026	Aug 2026 to Jul 2027	From Aug 2027
General, about 3.7M JPY or less	outpatient 18,000 (annual 144,000); household 57,600	outpatient 22,000 (annual 216,000); household 61,500	about 2.6M to 3.7M JPY: 28,000 and 69,600; about 2.0M to 2.6M JPY: 28,000 and 65,400; up to about 2.0M JPY: 22,000 and 61,500 (outpatient annual 216,000 in all three)
Residence-tax-exempt	outpatient 8,000; household 24,600	outpatient 11,000 (annual 96,000); household 25,700	outpatient 13,000 (annual 96,000); household 25,700
Residence-tax-exempt, income below a set level	outpatient 8,000; household 15,000	outpatient 8,000; household 15,700	unchanged

Amounts are in JPY, with outpatient caps per person and household caps per household (as of 2026-07-31).³ MHLW is still studying the age range for the outpatient special rule, following a 2025-11-21 cabinet decision, so the outpatient column may change.³

Readers in this group should check the ward or insurer page for their exact outpatient and household pair. The main tables above cover the under-70 case only.

Two ways to pay: certificate up front or refund later

The default route is post-payment refund: pay the 30 percent at the counter, then claim back the excess above the ceiling.¹ The pre-payment route caps the counter bill itself: present the Limit Application Certificate or use the My Number insurance card so the facility charges only up to the ceiling.¹¹⁰ Counter capping covers the monthly ceiling only: amounts above the annual cap are paid at the counter first and refunded by the insurer afterwards.⁷

The diagram below shows the choice as a resident experiences it.¹⁰

The 限度額適用認定証 (gendogaku tekiyo ninteisho, "Limit Application Certificate") is the paper certificate for facilities without online eligibility verification or where the My Number is not registered.¹⁰ At verified facilities, the マイナ保険証 (maina hokensho, "My Number card registered for health-insurance use") shares the ceiling electronically with no separate form.¹⁰² Residents without a My Number insurance card can instead show a 資格確認書 (shikaku kakuninsho, "eligibility certificate") that carries the optional ceiling-band entry, or the Limit Application Certificate.⁷

Low-income households use the combined 限度額適用・標準負担額減額認定証 (gendogaku tekiyo hyojun futangaku gengaku ninteisho, "combined ceiling and meal-charge reduction certificate") to unlock both the lower ceiling and reduced meal charges.¹⁰² Kyokai Kenpo tells low-income members aged 70 and over that this certificate procedure is required whether or not they can use the My Number insurance card.¹¹ A late certificate presentation can fail to apply to that bill, so arrange it before admission.⁶

Set up the My Number insurance link before planned admission

Registering the My Number card for insurance use removes the paper step at verified facilities. For a scheduled surgery or admission, confirm the link or request the certificate first rather than fronting the full 30 percent.¹⁰²

Where to apply by insurance type

Employees apply to their company health insurance society or Kyokai Kenpo branch, while National Health Insurance members apply at the municipal counter (as of 2026-07-01; confirm current figures with your insurer).¹¹⁰² In the ward example, the National Health Insurance benefit section handles online, mailed, and counter applications, with a phone check first for same-day issue.²

Post-payment claims run on a 2-year clock from the 1st of the month after treatment.⁵ In the ward example, the office mails a notice about 3 to 4 months after the treatment month, and transfer takes about 1.5 to 2 months after filing (as of 2026-07-01).⁵

Unpaid hospital bills cannot be paid out, and premium arrears can block certificate issuance as a rule.⁵² After one filing, the ward automates later payouts to the same account until the household head or account changes.⁵

What counts toward the cap

Only insured copayments count, never meals or private-room differentials.⁴ Counting runs per facility grouping: medical inpatient, medical outpatient, dental inpatient, and dental outpatient are tallied separately, with pharmacy dispensing added to the prescribing facility (as of 2026-07-01; confirm current figures with Kyokai Kenpo or your ward office).⁴⁵

Household members on the same insurance combine their copayments in the same month through 世帯合算 (setai gassan, "household aggregation").⁴ For residents under 70, only receipts of 21,000 JPY or more per facility grouping enter the combination (as of 2026-07-01).⁴⁵

Changing insurer, or changing from insured to dependent status, resets the 12-month multiple-occurrence count.⁴ Keep the same insurer record continuous where possible during long treatment.

Chronic treatment reduction

When ceiling-level months reach 3 or more within the prior 12 months including the treatment month, the 4th and later months use the lower 多数回該当 (tasūkai gaitō, "multiple-occurrence reduction") amount (as of 2026-07-31; confirm current figures with MHLW or your insurer).⁴⁵ For bracket ウ the reduced ceiling is 44,400 JPY both before and after the August 2026 revision (as of 2026-07-31).²⁴ From August 2027 the amount for the band of about 2.0M JPY or less (standard monthly remuneration 150,000 JPY or less; NHI income basis 860,000 JPY or less) falls from 44,400 to 34,500 JPY (as of 2026-07-31).³⁷

The August 2026 revision held every multiple-occurrence amount flat while raising the monthly bases; the August 2027 cut above is the only later change to those amounts (as of 2026-07-31).¹³ It also added a new 年間上限 (nenkan jogen, "annual cap") summed per household from August to next July, with the excess paid back (as of 2026-07-31).²

Current annual ceilings for under-70 households are 1.68M JPY for band ア, 1.11M JPY for イ, 530,000 JPY for ウ and エ, and 290,000 JPY for オ (as of 2026-07-31).²⁴ Within エ, members confirmed at about 2.0M JPY or less (standard monthly remuneration 150,000 JPY or less; NHI income basis 860,000 JPY or less) already get a 410,000 JPY annual cap for August 2026 to July 2027, refunded from August 2027 (as of 2026-07-31).³⁴ Annual caps count from the August 2026 treatment year, and Kyokai Kenpo opens annual-cap claims in August 2027, with the form not yet published (as of 2026-10-11).⁴

The second stage is fixed by cabinet order 令和8年政令第240号, promulgated on 2026-07-29, and takes effect on 2027-08-01 with the band subdivision and the lower multiple-occurrence amount for the lowest taxable band.⁸⁹³ MHLW describes the aim as finer income bands without sharp increases from current ceilings.¹

Separate long-term-disease relief covers dialysis-dependent renal failure, hemophilia, and specified antiviral treatment at 10,000 JPY per month, or 20,000 JPY for high-remuneration under-70 cases, through a specific-disease card.⁴ Ask the insurer about that card rather than the standard certificate when one of these diagnoses applies.

Good to know

A stay that straddles two calendar months counts twice

The ceiling resets on the 1st, so an admission spanning a month boundary draws one ceiling per month.² A single continuous stay can therefore cost two ceilings even though the treatment never paused.

Where the schedule is medically elective, starting early in the month concentrates covered cost under one ceiling. Confirm the plan with a licensed medical provider rather than shifting dates alone.

Private-room and meal charges have no cap

The differential bed charge, meal and living costs, and non-insured care carry no ceiling and stack on top of the capped amount.⁴⁵ Residents who budget only the monthly ceiling understate the real discharge bill.

Ask the hospital for the per-day bed differential and meal schedule at admission. Choosing a standard room where available keeps the uncapped portion smaller.

File the refund within two years

The refund window closes 2 years after the month following treatment, and unpaid hospital months cannot be paid out.⁵ Ward notices arrive months later, so track treatment months directly rather than waiting for the letter (as of 2026-07-01).⁵

Filing once usually automates later payouts to the same account.⁵ Report a household-head or account change promptly so automation does not misroute the transfer.

Confirm the current ceiling before planned treatment

Monthly bases rose in August 2026 while multiple-occurrence amounts stayed flat, and a cabinet order fixes the band subdivision from 2027-08-01 (as of 2026-07-31; confirm current figures with MHLW or your insurer).¹⁸⁹ A remembered 80,100 JPY base now understates the typical-income ceiling.

Check the MHLW page or your insurer at treatment time, and confirm which band the insurer assigned. Kyokai Kenpo certificates issued from August 2026 expire on 2027-07-31 at the latest, and members who still need one reapply from August 2027 (as of 2026-10-11).¹⁰ National Health Insurance members can confirm their certificate's validity with the ward or municipal office.

See also

• Maina-Hokensho: Health Insurance Card Going Digital
• What Insurance Doesn't Cover
• Clinic vs. Hospital: The Two-Tier System
• NHI Enrollment at the Ward Office
• Shakai Hoken Overview

References

Footnotes

1. Ministry of Health, Labour and Welfare (MHLW). 「高額療養費制度を利用される皆さまへ」. Updated 2026-07-31. https://www.mhlw.go.jp/stf/seisakunitsuite/bunya/kenkou_iryou/iryouhoken/juuyou/kougakuiryou/index.html ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³

2. Nerima Ward Office. 「入院等でこれから高額な医療費がかかる場合（限度額適用認定証の申請）」. Updated 2026-07-01. https://www.city.nerima.tokyo.jp/kurashi/nenkinhoken/kokuminkenkohoken/hoken_kyufu/madoguchi.html ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶ ↩¹⁷ ↩¹⁸ ↩¹⁹ ↩²⁰ ↩²¹ ↩²² ↩²³

3. Ministry of Health, Labour and Welfare (MHLW). 「高額療養費制度の見直しについて」 (PDF; ceiling tables for 令和8年8月～令和9年7月 and 令和9年8月～, and comparison table with notes ※1 and ※2), linked from the MHLW high-cost medical expense page. 2026. https://www.mhlw.go.jp/content/001726232.pdf ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶ ↩¹⁷ ↩¹⁸ ↩¹⁹ ↩²⁰ ↩²¹

4. Japan Health Insurance Association (Kyokai Kenpo). 「高額療養費」. https://www.kyoukaikenpo.or.jp/benefit/high_cost_medical_expenses/002/index.html ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶ ↩¹⁷ ↩¹⁸ ↩¹⁹

5. Nerima Ward Office. 「医療機関などで高額な医療費を支払ったとき（高額療養費の支給）」. Updated 2026-07-01. https://www.city.nerima.tokyo.jp/kurashi/nenkinhoken/kokuminkenkohoken/hoken_kyufu/kogaku_shikyu.html ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴

6. MHLW. "High-Cost Medical Expense Benefit (Eligibility Certificate for Ceiling-Amount Application)" English explainer PDF (en09.pdf), linked from the MHLW international health-care pages. https://www.mhlw.go.jp/seisakunitsuite/bunya/kenkou_iryou/iryou/kokusai/setsumeisiryo/dl/en09.pdf ↩ ↩²

7. Ministry of Health, Labour and Welfare (MHLW). Leaflet 「令和8年8月から高額療養費制度が見直されます」 (PDF, 2 pp.; ceiling table and Q&A), linked from the MHLW high-cost medical expense page. 2026. https://www.mhlw.go.jp/content/001725284.pdf ↩ ↩² ↩³ ↩⁴

8. Cabinet of Japan. 「健康保険法施行令等の一部を改正する政令」 (令和8年政令第240号), promulgated 2026-07-29. Official Gazette (官報) 号外第169号, p. 8 (secondary locator; free 官報 pages are available for a limited period). https://www.kanpo.go.jp/20260729/20260729g00169/pdf/20260729g001690008.pdf ↩ ↩² ↩³

9. Cabinet of Japan. 令和8年政令第240号 附則第一条 (施行期日: 2026-08-01, with the provisions in item 2 from 2027-08-01). Official Gazette (官報) 号外第169号, 2026-07-29, p. 67 (secondary locator; free 官報 pages are available for a limited period). https://www.kanpo.go.jp/20260729/20260729g00169/pdf/20260729g001690067.pdf ↩ ↩² ↩³

10. Japan Health Insurance Association (Kyokai Kenpo). 「限度額適用認定証」. https://www.kyoukaikenpo.or.jp/benefit/high_cost_medical_expenses/001/ ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸

11. Japan Health Insurance Association (Kyokai Kenpo). よくあるご質問 「医療費が高額になりそうなとき（限度額適用認定証等）」. https://www.kyoukaikenpo.or.jp/faq/benefit/003/index.html ↩